1.按年份分组
select to_char(exportDate,'yyyy'),sum(amount) from table1 group by to_char(exportDate,'yyyy');
select to_char(exportDate,'yyyy-mm'),sum(amount) from table1 group by to_char(exportDate,'yyyy-mm')
order by to_char(exportDate,'yyyy-mm');
select to_char(exportDate,'yyyy-Q'),sum(amount) from table1 group by to_char(exportDate,'yyyy-Q')
order by to_char(exportDate,'yyyy-Q');
select to_char(exportDate,'yyyy-IW'),sum(amount) from table1 group by to_char(exportDate,'yyyy-IW')
order by to_char(exportDate,'yyyy-IW');
select sysdate-((1/24)/12) from dual
----结果减去5分钟
select sydate-(level-1) from dual connect by level<=10
---结果是10间隔1天的时间
下面是本次例子：
select dt, count(satisfy_degree) as num from T_DEMO i ,
(select sysdate - (level-1) * 2 dt
from dual connect by level <= 10) d
where i.satisfy_degree='satisfy_1' and
i.insert_time<dt and i.insert_time> d.dt-2
group by d.dt
例子中的sysdate - (level-1) * 2得到的是一个间隔是2天的时间
group by d.dt 也就是两天的时间间隔分组查询
select (sysdate-13)-(level-1)/4 from dual connect by level<=34 --从第一条时间记录开始（sysdate-13）为表中的最早的日期，“34”出现的分组数（一天按每六个小时分组 就应该为4）
一下是按照每6个小时分组
select mobile_no,area_name,max(created_time ),dt, count(*) as num from a_hy_locate1 i ,
(select (sysdate-13)-(level-1)/4 dt
from dual connect by level <= 34) d
where i.locate_type = 1 and
i.created_time<dt and i.created_time> d.dt-1/4
group by mobile_no,area_name,d.dt
另外一个方法：
--按六小时分组
select trunc(to_number(to_char(created_time, 'hh24')) / 6),count(*)
from t_test
where created_time > trunc(sysdate - 40)
group by trunc(to_number(to_char(created_time, 'hh24')) / 6)
--按12小时分组
select trunc(to_number(to_char(created_time, 'hh24')) / 6),count(*)
from t_test
where created_time > trunc(sysdate - 40)
group by trunc(to_number(to_char(created_time, 'hh24')) / 6)
